1. Technical Field
The present invention relates to a vehicle steering column including a steering wheel, which is pivotable between different positions. In particular, the present invention relates to a mechanism for locking a tilt steering wheel in a particular position.
2. Description of the Prior Art
It is known to provide a steering column with a releasable locking mechanism, which locks the steering wheel in one of a plurality of different tilted positions relative to the vehicle steering column. The locking mechanism can include members releasably clamped together to prevent tilting movement of the steering column member.
It is known to use an electrorheological magnetic fluid in an energy absorber for an engine mount or another structure having two relatively movable parts. Varying the strength of a magnetic field acting on the fluid can vary the shear strength and viscosity of the fluid, thus controlling the energy absorption characteristics of the device.
The present invention is an apparatus for supporting a steering wheel of a vehicle. The apparatus comprises a first steering column part and a second steering column part adjacent the first steering column part. The first steering column part and the vehicle steering wheel are supported for pivotal movement about an axis between a plurality of different orientations relative to the second steering column part. A locking mechanism is interposed between the first steering column part and the second steering column part for locking the first steering column part in a selected one of the plurality of orientations. The locking mechanism comprises a fluid having a shear strength which varies in response to an energy field acting on the fluid. The apparatus further comprises means for varying the shear strength of the fluid by varying the energy field to vary the resistance to movement of the first steering column part relative to the second steering column part.